Cable operators have widely deployed high-speed data services on cable television systems. These data services include a cable modem that allows a computer to communicate over an ordinary cable TV network Hybrid Fiber Coax (HFC) cable. A Cable Modem Termination System (CMTS) connects the cable TV network to a data network, such as the Internet. The Data Over Cable Service Interface Specification (DOCSIS) is one of the cable modem standards used for transferring data over the cable TV network.
Modular CMTSs (M-CMTSs) have been developed to improve scaling and for other reasons. These modular systems typically include an M-CMTS core device implementing a subset of DOCSIS protocol (such as Media Access Control (MAC) layer, etc.) and one or more remote PHYs such as an Edge Quadrature Amplitude Modulation (EQAM) implementing the remaining subset of DOCSIS protocol (such as the PHYsical layer (PHY), etc.) These remote PHYs generally include modulation devices for modulating downstream traffic to the cable modems or demodulation devices for demodulating upstream traffic from the cable modems. The M-CMTS core and the remote PHYs may communicate over a Downstream External Physical Interface (DEPI).
These M-CMTS cores and remote PHYs generally communicate with each other over an Internet Protocol (IP) or Ethernet network. Such networks have limited mechanisms for guaranteeing Quality of Service (QoS) or reserving bandwidth. These limitations become a problem, particularly when the networks either approach or surpass full bandwidth capacity. The disclosure that follows solves these and other problems.